with 'DX::Role::Step';
+#has resolution_space => (is => 'ro', isa => ResolutionSpace, required => 1);
+
sub apply_to {
my ($self, $ss) = @_;
- my ($first_alt, @rest_alt) = @{$ss->alternatives};
- return $ss->but(next_step => $ss->on_exhaustion_step) unless $first_alt;
- trace 'search.backtrack.rewind_to' => $first_alt->[1];
- return $ss->but(
- current_hypothesis => $first_alt->[0],
- alternatives => \@rest_alt,
- next_step => $first_alt->[1],
- is_solution_state => 0,
- );
+ trace backtrack => [ statement => [ [ symbol => 'backtrack' ] ] ];
+ foreach my $adj (@{$ss->decisions_taken}) {
+ my ($rspace_was, $ss_was) = @$adj;
+ next unless @{$rspace_was->remaining_resolution_space->members};
+ trace rspace => [ statement => [
+ [ symbol => 'remaining' ],
+ @{$rspace_was->remaining_resolution_space->for_deparse->[1]}
+ ] ];
+ return $ss_was->but(
+ next_step => $rspace_was->remaining_resolution_space->next_step
+ );
+ }
+ return $ss->but(next_step => $ss->on_exhaustion_step);
}
1;